Preparation method of continuous fiber reinforced nylon-6 composite material

Abstract

The invention discloses a preparation method of a continuous fiber reinforced nylon-6 composite material, which comprises the following steps: (1) separately storing caprolactam molten masses containing a catalyst and a catalyst promoter in a constant-temperature constant-speed liquid feeding tank; (2) placing a continuous fabric in a mold of an injection molding machine; (3) starting the injection molding machine and a constant-temperature liquid feeding device separately, adding the caprolactam molten masses containing the catalyst and the catalyst promoter into the feeding hole of the injection molding machine through the liquid feeding device at a same temperature and a same speed, mixing and injecting in the mold injection machine, and injecting the caprolactam molten masses containing the catalyst and the catalyst promoter into the mold paved with the continuous fabric; and (4) initiating caprolactam negative ring-opening polymerization in the mold. The preparation method disclosed by the invention can effectively prevent caprolactam from polymerization before entering the mold, so as to ensure good impregnation of fiber and caprolactam to obtain the continuous fiber reinforced nylon-6 composite material with more excellent mechanical properties.

Description

technical field [0001] The invention belongs to the field of material preparation, in particular to a method for preparing a continuous fiber reinforced nylon 6 composite material, in particular to a method for preparing a continuous fiber reinforced nylon 6 composite material through resin transfer molding based on anionic ring-opening polymerization. Background technique [0002] Due to the inherent shortcomings of thermosetting resin-based composites such as fracture toughness, low damage tolerance, moisture absorption, poor environmental adaptability, long production cycle, and difficulty in recycling, thermoplastic resin-based composites have made great progress in recent years. Among them, glass fiber, carbon fiber, basalt fiber and aramid fiber are used to reinforce nylon 6, and then the polyamide matrix is ​​further toughened by fiber structure optimization, mixing, and fiber surface treatment. The prepared fiber reinforced nylon 6 composite Materials have been widel...

AI Technical Summary

Problems solved by technology

The impregnation of the fiber by the caprolactam melt is a crucial factor affecting the performance of the composite material. However, in the existing patents, the caprolactam melt before entering the mold usually contains both a catalyst and a co-catalyst, and the melt is transported to the mold. During the process, melt polymerization or crystallization is usually prone to phenomena that are not conducive to melt flow, which will have a negative impact on the impregnation of fibers and melt, thereby deteriorating the mechanical properties of the composite material; secondly, use the vacuum suction method to inject into the mold The technology of caprolactam melt is very easy to cause boiling and sublimation of caprolactam melt, which usually introduces pores or defects inside the composite material, which will also deteriorate the performance of the composite material; in addition, in the process of preparing continuous fiber reinforced nylon 6 by RTM, When the caprolactam in the mold starts anionic polymerization to form nylon 6, due to the crystallization process of nylon 6, it usually causes the composite material inside the mold to shrink, so that the mold will no longer compact the composite material tightly, and will also cause defects such as holes in the composite material , however, there is no patent technology or literature report on overcoming such problems

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